A computational fluid dynamics model of a dairy holding area

Abstract. The design and operation of ventilation systems for animal housing is a crucial component in maintaining a suitable environment of both animals and workers by removing heat, moisture, and gas species. However, important design and operational criteria such as profiles of velocity and extent of mixing within animal housing can be difficult to study experimentally. Thus, a computational fluid dynamics (CFD) model of a commercial dairy holding area including the generation of transport of heat and gas species within the domain was developed. The animal occupied zone was modeled using porous media. The model was validated with experimental data of velocity and gas concentration. Results indicated that the uniformity and air speed could be increased within the holding area by modifying the configuration of side curtain openings and use of concrete walls to guide airflow; a 20% increase in average velocity within the animal occupied zone was achieved. Results of the CFD model have shown it to be in effective tool in gaining insight to the complex mixing patterns within holding areas to improve design.